Materials Data on SmSiNi4 by Materials Project

SmNi4Si is Frank-Kasper $\mu$ Phase-derived structured and crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Sm is bonded in a 6-coordinate geometry to fourteen Ni and four equivalent Si atoms. There are a spread of Sm–Ni bond distances ranging from 2.84–3.14 Å. All Sm–Si bond lengths are 3.24 Å. There are two inequivalent Ni sites. In the first Ni site, Ni is bonded in a 12-coordinate geometry to three equivalent Sm, five Ni, and two equivalent Si atoms. There are four shorter (2.48 Å) and one longer (2.59 Å) Ni–Ni bond lengths. Both Ni–Si bond lengths are 2.36 Å. In the second Ni site, Ni is bonded to four equivalent Sm, six Ni, and two equivalent Si atoms to form NiSm4Si2Ni6 cuboctahedra that share corners with four equivalent SiSm4Ni8 cuboctahedra, corners with twelve equivalent NiSm4Si2Ni6 cuboctahedra, edges with four equivalent SiSm4Ni8 cuboctahedra, edges with six equivalent NiSm4Si2Ni6 cuboctahedra, faces with four equivalent SiSm4Ni8 cuboctahedra, and faces with six equivalent NiSm4Si2Ni6 cuboctahedra. Both Ni–Ni bond lengths are 2.57 Å. Both Ni–Si bond lengths are 2.44 Å. Si is bonded to four equivalent Sm and eight Ni atoms to form distorted SiSm4Ni8 cuboctahedra that share corners with eight equivalent NiSm4Si2Ni6 cuboctahedra, corners with eight equivalent SiSm4Ni8 cuboctahedra, edges with two equivalent SiSm4Ni8 cuboctahedra, edges with eight equivalent NiSm4Si2Ni6 cuboctahedra, faces with two equivalent SiSm4Ni8 cuboctahedra, and faces with eight equivalent NiSm4Si2Ni6 cuboctahedra.